Could be a few things for 1. your Cron Job may be not set up correctly or 2. you have something wrong with Ajax i heard that Ajax is responsible for video possessing but Ajax runs with your Cron Job The Cron Job keeps time and then initiates commands based on the time you set mines runs every minute of every day that's preferable other things that it could be for one is changing the code for the script i.e your website in anyway.

anyways Alex T⚜️ Alexey Anton L  may be able to help you here